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Tufail,
It doesn’t seem logical at all !
So there is no explanation for it, except maybe to assume that, with RXLEV ACCESS MIN = -96dBm, you’re forbidding calls with rxlev < -96dBm and with a GOOD quality, while still allowing calls with -90dBm but POOR quality... perhaps 🙂 That might just be the case for some cells, but not all of them.
Hi Pix,
thanks.
I thinks that is the case.
regards
TufailHii All,
Plzz Anybody can explain me about CA & BA in TEMS, about MAIO and what is difference between RxQual sub & RxQual Full?
Actually diff. between sub and full.
Looking for reply.
BR
Sambitwhat is difference between RxQual sub & RxQual Full?
Hii all,
Plzz any body can tell me about BA, CA and about MAIO.
Waiting for reply.
BR
SAMBITHi ahmed,
FULL – Sub is corresponding to DTX OFF – DTX ON
Hi PIX,
How would one know that the SDCCH congestion is due to the ghost Rach.Hi PRO,
Some time when neighbours parameters are not defined properly, then H.O shows 100% Failure.For eg. at the time of IP creation for site CI:10011 you have defined BCCH:112, BSIC:10 & LAC:201, but at the time of neghbour creation CI:10011 is the neighbour of CI:10021 & by mistake you difined parameters for CI:10011 is BCCH:111 instead of 112 or you defined wrong BSIC & LAC etc then thier is a 100% h.o filure. Sp plz check your neighbour databse first.Regards,
NitinHello nachi,
you may detect Phantom RACH from Timing Advance measurments since you will notice samples from impossible distances.
ex: i made a drive test for a cell that can barely cover 5 KM, and I had High SDCCH assignment failure, from timing advance measurments it reported many samples from 20Km and 26Km which was impossible! therefore increasing RxLEvAccessMin from -108 to -106 made a lot of improvement in the sdcch assignment success rate (from 40% to 10%)da architect,
the TA measurements were performed on the Abis, isn’t it ? It looks like it is the only way to ensure those are ghost RACH.
With other methods, you can only assume that they are…
for instance, if you see a constant amount of SDCCH assign failure due to radio, at any hour during the day, you can safely assume those are due to ghost rach…Regards,
hi guys,
A phantom RACH? Is it a real problem or just a good exist from the problem ? everything has a reason so what is the source of ghost RACH? hardware or radio? and how?
Architec,
as I know TA is measuring the distance of the MS’s based on the signal trip time. I mean it is not a direct distance measure; it just measure the distance by multiplying the time by the speed of the signal. Your high TA maybe caused by the fast cars moving away from the site !Akefa,
That’s a good one 🙂 The timing advance does not depend on the speed of the mobile !! It is a measure of the real distance between MS and BTS, by using the delay in propagation. The speed of a EM wave is 300.000km/h. A car moving a 300km/h would not change a thing here…
Ghost RACH are usually an effect of hardware distubances, or maybe fluctuations of EM in the atmosphere ?? Anyway, the ghost RACH contains dummy information, and the TA of a ghost RACH is “unrealistic”.
Pix,
Maybe there are rockets 😀
You are right !It is amazing for me to see some people here talking about tunning t3101 ! It seems only in Erricsson, this timer is unchangable !! Am I right ? My boss told me it is a fixed value !!
Never trust your boss… It is changeable in alcatel, and in most systems i think.
thanx Pix
I will do myself more efforts to prove it.
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